Rotary magnetic recording-reproducing apparatus

ABSTRACT

A magnetic recorder or reproducer in an electronic camera system wherein a subject is pure-electronically still-photographed and recorded on a rotating magnetic disc, and the reproducing of an image is carried out by a television system or a printer. 
     In this rotary magnetic recording-reproducing apparatus, the addressing of tracks is performed under two modes including absolute addresses and relative addresses, so that the most proper mode can be used in accordance with the purpose of use of the track addresses. Particularly, the adverse influence of a shift in the addressing due to a dropout can be eliminated and a shift in the numbering when the track number is displayed can be also eliminated.

BACKGROUND OF THE INVENTION

1. Field of the Invention

This invention relates to a rotary magnetic recording-reproducingapparatus, and more particularly to a rotary-magneticrecording-reproducing apparatus for reproducing information recorded ina rotary magnetic recording medium such as a magnetic disc. Especially,this invention relates a rotary magnetic recording-reproducing appartuswherein information recorded on tracks formed concentrically on themagnetic disc is reproduced with a tracking servo being applied thereto.

2. Description of the Prior Art

Recently, there has been developed an electronic still camera systemwherein an image pickup device such as a solid state image sensingdevice or an image pickup tube is combined with a recording device usingan inexpensive magnetic disc as a recording medium and yet having acomparatively high memory capacity, a subject is stillphotographedpurely electronically and recorded into a rotating magnetic disc, andthe reproduction of an image is carried out by a television, a printeror the like, which are provided separately.

However, the recording medium used in the above-described magneticrecording, particularly, the magnetic disc tends to cause a trackingfailure due to anisotropy, eccentricity, thermal expansion and the like.Consequently, there is such a disadvantage that a track adjacent apredetermined track is scanned during reproduction, whereby a crosstalkis caused.

To obviate this disadvantage, a tracking signal is recorded with atracking servo being applied during recording of information, and duringreproduction the tracking servo is applied by use of the trackingsingnal. However, it is impracticable to provide a tracking servomechanism requiring highly accurate control on a recording apparatusbeing compact in size and light in weight, such as a camera.

Firstly, there is such a method that, as the recording system, a guardband system or an FM azimuth system is adopted and the tracking failureoccurring to some extent during reproduction is compensated in such amanner that a reproducing head does not scan the adjacent track and,even if the reproducing head scans, the reproducing head does not pickup a signal of the adjacent track.

Along with the above, a so-called peak searching system is used, whereinduring recording a recording head is transferred at a predeterminedtrack pitch by a stepping motor without the tracking servo beingapplied, during reproduction enveloped of output signals of respectivetracks are detected, the optimal track is discriminated from a positionof peak and the tracking servo is applied.

In the rotary magnetic recording used in the electronic still camerasystem, 50 tracks are recorded on a disc having a diameter as small asabout 50 mm at a track pitch of about 100 μm, i.e. a track width ofabout 50˜60 μm and a guard band width of about 50˜40 μm for example. Inthe recording or reproducing apparatus, this magnetic disc rotated at aconstant speed of 3000 rpm for example, and image signals are recorcdedor reproduced at a field or frame speed.

The above-described compact magnetic disc being thin and having thesmall diameter is normally housed in a mold package (hereinafterreferred to as a "disc pack") made of plastics, etc. for handling.Namely, each disc pack is loaded in a loading position of a recording orreproducing apparatus, whereby the magnetic disc, housed in the discpack, is rotatably driven for recording or reproduction.

Now, in the rotary magnetic recording-reproducing appratus, it isnecessary to display a track number upon completion of the tracking oneach of the tracks. In such a case as described above, the handling ofthe tracks matters when there is a dropout track or an unrecorded track.In the rotary magnetic recording-reproducing apparatus, if the dropoutof a signal occurs in a track of the magnetic disc for example, thetrack may be skipped and the succeeding perfect track may be recorded.In other words, in the reproducing apparatus wherein a track number isdiscriminated simply on the basis of the transferred distance of thereproducing head, even a defective track, in which no image signal isrecorded, is discriminated as if an effective track and the track numberthereof is displayed. In consequence, inconvenience may occur in theoperation of such a reproducing apparatus that an image of a desirableframe number is to be rapidly selected and displayed. Namely, in thecase of users, it suffices to number-display the recorded trackssuccessively. Reproduced images can be displayed on the display screenin accordance with the number displays, thus enabling to avoid giving afeeling of disorder to the users.

However, if all of the handlings are made by such an addressing asdescribed above, namely, skipping the defective tracks, the followingdisadvantage will be presented. Namely, in the reproducing apparatus ofthe type wherein the reproduction is performed with the unrecorded trackor tracks being skipped, such a disadvantage may be presented that, whenit is desired to know what is recorded in a certain track irrespectiveof the quality of the record to some extent or when it is desired toknow as to whether a certain track is judged as an unrecorded track andskipped because of a defectively recorded state of something or of norecording being made entirely, the track cannot be observed.

SUMMARY OF THE INVENTION

The present invention has been developed to obviate the disadvantages ofthe prior art and has as its object the provision of a rotary magneticrecording-reproducing apparatus wherein the addressing of tracksprovided on a rotary magnetic recording medium is set in a plurality ofmodes in accordance with the uses.

To this end, the present invention contemplates that, in a rotarymagnetic recording-reproducing apparatus including: a magnetic head forreading signals from a plurality of tracks each formed into a locus inwhich relative positions of a leading end and a tail end of a recordingcoincide with each other on a rotary magnetic recording medium; headmoving means for transferring the magnetic head onto a desirable one ofthe tracks; and control means for controlling the head moving means tomake the tracking on an aimed track; the apparatus further includesaddress setting means wherein absolute addresses and relative addressesare simultaneously used to make the addressing from the first track tothe final track.

BRIEF DESCRIPTION OF THE DRAWINGS

The exact nature of this invention, as well as other objects andadvantages thereof, will be readily apparent from consideration of thefollowing specification relating to the accompanying drawings, in whichlike reference characters designate the same or similar parts throughoutthe figures thereof and wherein:

FIG. 1 is arrangement drawing showing the outer appearance of the rotarymagnetic recording-reproducing apparatus according to the presentinvention;

FIG. 2 is a block diagram showing the circuit arrangement of the rotarymagnetic recording-reproducing apparatus according to the presentinvention;

FIG. 3 is a perspective view showing an example of the magnetic discpack usable in the apparatus shown in FIG. 1;

FIGS. 4A and 4B are explanatory views showing the portion for loadingthe disc pack of this apparatus;

FIG. 5 is an explanatory view showing the arrangement of the tracks inthe magnetic disc applicable to this apparatus;

FIGS. 6A to 6E are flow charts showing examples of operation flows ofthe control device shown in FIG. 2;

FIGS. 7A to 7E are flow charts showing sub-routines of the controldevice;

FIG. 8A is a explanatory views showing absolute addresses; and

FIG. 8B is a explanatory views showing relative adresses.

DETAILED DESCRIPTION OF THE INVENTION

Detailed description will hereunder be given of the preferred embodimentof the rotary magnetic recording-reproducing appratus according to thepresent invention with reference to the accompanying drawings.

FIG. 1 shows an arrangement drawing showing the outer appearance of therotary magnetic recording-reproducing apparatus 100 according to thepresent invention. Referring to FIG. 1, designated at 1 is a casing, 2 apower source switch, 4 an eject switch, 5 a forward switch for feedingthe magnetic head in the forward direction, 6 a reverse switch forfeeding the magnetic head in the reverse direction, and 7 a track numberdisplay switch for showing that in which track on the magnetic disk themagnetic head is positioned. Furthermore, denoted at 8 is a warning lampformed of a LED (light emitting diode) or the like, 9 a connector forremote control and 102 a bucket to be opened by the eject swith 4.

FIG. 2 shows the circuit arrangement of the apparatus of this embodimentillustrated in FIG. 1, wherein a rotary recording medium 10, such as forexample a magnetic disc, is detachably mounted to a spindle 14 driver bya DC (direct current) motor 12. In this embodiment, the magnetic disc 10has a sheet of a magnetic recording material having a diameter of about50 mm. Recorded on a recording surface 16 are a plurality of, such forexample as 50, recording tracks on concentric circles at a pitch ofabout 100 μm for example. In this embodiment, signals recorded on therecording tracks are image signals, which may be color image signals FMmodulated from brightness signals and chrominance signals for example.This image signal may be a field image signal forming a field of imagethrough raster scanning, which is recorded on each of the tracks.

The DC motor 12 has a frequency generator 18 generating AC (alternatingcurrent) frequency signals, receives power supply from a power sourcethrough a servo circuit 20 and servo-controlled in such a manner thatthe disc 10 is rotated at a predetermined speed of rotation, e.g. aconstant speed of 3600 rpm. The servo circuit 20 is connected to acontrol device 60 for controlling the apparatus as a whole. The controldevice 60 is operated in accordance with a signal disc to control therotatable driving and stop of the disc 10.

A phase generator 22 is provided at a position close to the recordingsurface 16 of the disc 10 and connected to the servo circuit 20 and thecontrol device 60 through an amplifier 24. With this arrangement, atiming mark formed as opposed to a predetermined position on therecording surface 16 is detected, and timing pulses PG are formed.

A magnetic transducer, i.e. magnetic head 26 is provided on therecording suface 16 and carried by a supporting mechanism 28. Asconceptually indicated by a broken line 28, this supporting mechanism isdriven by a step motor (PM) 30, moves the magnetic head 26 along therecording surface 16 in opposite radial directions as indicated by adouble-headed arrow R, and can select an optional track on the recordingsurface 16.

The magnetic head 26 may have a magnetic recording function, however, inthis embodiment, such a magnetic head is exemplified which has areproducing function of detecting an image signal from a track which hasbeen recorded on the recording surface 16 and transducing the same intoan electrnic signal associated therewith. In this embodiment, asdescribed above, the disc 10 is rotated at the constant speed of 3 600rpm, whereby an image signal for one track, i.e. FM modulated imagesignal of one field is reproduced by the magnetic head 26 every 1/60SEC, per turn. This means that the demodulation of the image signalmakes it possible that this embodiment becomes compatible with astandard color television system such as the NTSC (National televisionsystem committee) system.

A reproducing output 32 of the magnetic head 26 is connected to an imagesignal processing circuit 36 and an envelope wave detecting circuit 38through a pre-amplifier 34. The image signal processing circuit 36 issuch a circuit that an image signal detected by the head 26 issignal-processed and the signal thus processed is outputted to anapparatus output 40 as a composite color image signal of a NTSC format.The processing circuit 36 has functions of demodulating this signal,extracting a vertical synchronizing signal VSYNC from the compositecolor image signal of the NTSC format and feeding the same to thecontrol device 60. Furthermore, the processing circuit 36 receives asignal MUTE from the control device 60 and converts and effectivehorizontal scanning time duration of the image signal into a blanksignal, thereby performing a muting operation. It is not essential forthis apparatus to have a function of converting the image signal intothe standard format, and the processing circuit 36 may have the functionof synchronous extraction from the image signal sensed by the head 26and the function of outputting the same to a terminal 40 simply by thecontrol device 60.

The envelope wave detecting circuit 38 is such a wave detecting circuitwhich detects an envelope of the FM modulated image signal recorded on atrack of the recording surface 16 and outputs a voltage commensuratethereto to an output 42. This ciruit 38 is connected to ananalogue-digital converter (ADC) 46 through an envelope amplifier 44. Inthis embodiment, the ADC 46 has a quantization leved of 256 and outputsto the control device 60 as data to eight bits at request of the controldevice 60.

As will be described in detail hereunder, the control device 60 is sucha control device which generalizes the control of this apparatus as awhole under the opration of the operator and is advantageouslyconstituted by a micro procesor system for example.

As described above, this embodiment includes the power source switch 2,the forward key FWD 5 for transferring the head 26 in the forwarddirection of the track number (for example, from a track disposed at theouter side to another track disposed at the inner side) and the reversekey REV 6 for transferring the head 26 in the reverse direction, and allof which are connected to the control device 60. The track number 49,where the magnetic head, which has been fed by the key FWD 5 or REV 6,is positioned, is visibly displayed on an indicator 48 such as a CRTdisplay or the like by a superimposer, etc. having an oscillator, notshown, connected to the control device 60. The track number 49 may bedisplayed on an indicator provided independently of the indicator 48 butnot on the indicator 48.

In this embodiment, the step motor 30 is a pulse operated motor of fourphase driving, and rotated through about 15° per driving pulse. Inconsequence, the step motor 30 makes one turn by 24 pulses. The headsupporting mechanism 28 is constructed such that the head 26 istransferred by about 4.2 μm in a direction indicated by the arrow R byone pulse fed to the step motor 30. A time duration of excitation forone pulse is about 2˜3 millisec for example. In consequence, the head 26is transferred about 100 μm by 24 pulses.

These driving pulses are fed from a driving circuit 50 comprising acurrent amplifier, and the driving circuit 50 produces excitation coildrivng pulses of the step motor 30 in accordance with an excitationpattern instructed by the control device 60.

The control device 60 and the servo circuit 20 are operated inaccordance with a standard clock generated by an oscillator of standardclock (OSC) 62. In this embodiment, the servo circuit 20 is bed theretowith a standard signal of 60 Hz equal to the field frequency of theraster scanning image signal recorded in the magnetic disc 10, and thecontrol device 60 is fed thereto with a clock of as high as 3.58 MHz forexample.

FIG. 3 shows a magnetic disc pack 200 used in this embodiment. This discpack 200 has a casing 222 rotatably receiving therein the magnetic disc10 being thin and having a small diameter, for the image signal.Provided substantially at the center of the casing 222 is a circularopeing 226, through which is exposed a hub or a core formed at thecenter of the magnetic disc 10. A positon of a core 212 is provided witha magnetic material 214 for exciting the coil 22 of the phase generator.

When the disc pack 200 is mounted to a magnetic recording apparatus 100,the forward end portion of the spindle 14 thereof is chucked by the core212, so that the magnetic disc 10 can be rotated in the disc pack 200.

The disc pack 200 is provided with a shutter 230 movable in directionsin paralled to one side of the disc pack 200 as indicated by adouble-headed arrow 228. When this shutter 230 is moved to a positionopposite to the position as shown, an opening of the casing 222 disposedthereunder is exposed, so that an adjusting plate 64 and the magnetichead 26 of the reproducing apparatus 100 can be approached or abuttedagainst the magnetic disc 10.

As shown in FIG. 4A, the disc pack 200 receiving therein the disc 10 isinserted into a bucket 102 thereof in order to be loaded in thisapparatus 100. Tht bucket 102 detachably receives therein the disc pack200 and holds the same, and supported in the casing 1 of this apparatus100 in a manner to be rotatable about an intersection 104. The bucket102 is normally biased by biasing means 106 in a direction opposite todirection indicated by an arrow A, so that the disc pack 200 can betaken out of the bucket 102 at a position shown in FIG. 4A.

When the disc pack 200 is inserted into the bucket 102 and the bucket102 is pushed in the direction indicated by the arrow A, an engageablemember 108 is operated in association therewith, the bucket 102 slidesin a direction indicated by an arrow B on one side 116 of an arm 112rotatable about a fulcrum 110 in a direction indicated by an arrow C bybeing biased as shown in FIG. 4B, and moves to a position indicated by abroken line 108a. Then, when the hand is removed from the bucket 102,the bucket 102 is brought into an accurate boading position by thebiasing pressure of biasing means 106, and the engageable member 108 isreceived into an engageable groove 114 formed at the forward end of thearm 112 to be engaged therewith.

At this time, the core 212 of the disc 10 accurately chucks the spindle14.

In this state, a pressing portion 118 disposed at the other end of thearm 112 presses a projection 128 of a normalyopen contact point 120 toclose the same. Namely, the contact point 120 is closed only when thebucket 153 is in the normally loaded state. As shown in FIG. 2, anoutput terminal 130 is connected to the control device 60, so that thecontrol device 60 can detect wheter the disc pack 200 is normally loadedor not. As described above, the contact point 120 consitutes a loadswitch shown in FIG. 2.

Furthermore, the bucket 102, is formed at the lower portion thereof withan opening 122 as indicated by broken lines. Therefore, when the bucket102 comes to the normal loaded position, a projection 126 of anormally-open contact point 124 enters the opeing 122 and abuts againstthe disc pack 200, whereby the disc pack 200 is pressed to close thecontact point 124. If the disc pack 200 is not inserted into the bucket102 in the normal state, the contact point 124 is not closed. As shownin FIG. 1, an output terminal 132 of the contact point 124 is connectedto the control device 60, so that the control device 60 can detect thepresence of the disc pack 200. As described above, the contact point 124constitutes a pack switch shwon in FIG. 2.

As shown in FIG. 5, in this embodiment, respective tracks of themagnetic disc 16 are arranged from a junior number at the outside to asenior number at the inside, whereby the home position HP, i.e. areturning initial position of the magnetic head 26 is set at a positionoutwardly of the track No. 1 disposed at the outer-most side. Selectionof a track or control of tracking is performed as referenced from thisreference position, i.e. the returning initial position HP and bycounting the number of tracks, i.e the number of peakes of the envelope,as the head is transferred.

An address is given to each of the tracks No. 1 to No. 50 whereby themovement of the magnetic head is controlled. The addresses are set forcontrol as described above, so that necessity of making the mechanicalpursuit of the track is eliminated, thus enabling to reduce the numberof parts. The method of setting the addresses includes two systemsincluding a relative address system and an absolute address system.Normally, the control is carried out by use of the relative addresses,and not normally, the control is carried out by use of the absoluteaddresses. In consequence, the both systems of address setting are usedsimultaneously.

As shown in FIG. 8(A), according to the absolute address setting, theinitial No.1 track contiguous to the head position (HP) is made to bethe address 1, and thereafter, addresses by consecutive numbering aresuccessively given up to No. 50. Since these addresses correspond to thetracks No. 1 to No. 50 in a ratio of one to one, the envelope detectionsignals obtainable during tracking cannot be utilized. Because of this,the number of pulse signals for driving the pulse motor (PM) 30 iscounted, to thereby enable to index the number of addresses.

On the other hand, as shown in FIG. 8(B), according to the relativeaddress setting, the address 1 is set to No. 1 track. However, in thecase where the magnetic head 26 makes the tracking of the trackssuccessively, when No. 3 track is dropped, as shown, for example, thesucceeding No. 4 track is set to address 3. In consequence, should nodrop occur, the absolute addresses coincide with the relative addresses.

The following is the tracking by a peak searching control. Firstly,assumption is made that the magnetic head 26 has been located on atrack. When the key FWD 5 or the key REV 6 is operated, the controldevice 60 starts the step motor 30 through the driving circuit 50 tothereby transfer the magnetic head 26 in the forward or reversedirection.

In this embodiment, in the first place, the magnetic head 26 istransferred a distance slightly shorter than a pitch between tracks of100 μm, e.g. a distance for 23 pulses, i.e. about 96 μm in the forwardor reverse direction. As this time, as for the signal read by themagnetic head 26, an envelope is wave-detected by the envelope wavedetecting circut 38 and inputted to the control device 60 as digitaldata from the ADC 46. Then, the control device 60 further transfers thehead 26 by one pulse, and the level of a signal detected from themagnetic head 26 then is compared with that of the preceding envelope.

While tranferring the head 26 as described above, the control device 60detects and compares the envelope level each time and judges theposition of the peak of the envelope. The position of the head where thepeak is detected is a position of an accurate on-track. Thus, thecontrol device 60 performs the peak searching tracking.

In order to rapidly one-track the head at a normal track position duringthe peak searching track, it is desirable that the magnetic head 26 isreturned to the returning intial position HP at least before the startof tracking.

FIGS. 6A and 6E are flow charts showing the control due to the switchoperations of the respective sections according to the presentinvention. (Additionally, the numerals in the parentheses indicate thestep numbers or processing rotes). When the power switch 2 is turned onfirstly, reset is made (300), and the contents of memory which have beenaccumulated so far are cleared due to RAM clear (302). Subsequently, sixswitches, i.e. the pack switch (Pack SW) 124, home position switch(HP.SW) 125, load switch (Load SW) 120, forward switch (Fwd SW)5,reverse switch (Rev SW) 6 and track number switch (Tr No.SW) 7 arescanned at pulses of 1v by key scan (304). More specifically, the pulsesof 1v scans the routines from flow 306 to flow 309 at a cycle of 1/20sec, to thereby grasp the on-off operations of the above-described sixkeys at every 1/60 sec.

Description will hereunder be given of the warning processing when theforward button 5 or the reverse button 6 is pressed with the magneticdisc pack 200 being not mounted to the main body of apparatus. Firstly,when the pack switch 124 is judged to be off by the key scan startedfrom Step 304 (310) in Step 308, judgment is made as to whether the homeposition switch is on or not in Step 312. Since the head 26 is not yetreturned to the starting end position (HP position) when the homeposition switch 125 is off, the head 26 is fed in the reverse directiontoward the home position switch by the reverse feed of the head (314).When the head 26 reaches the home position, judgment obtained by the keyscan in Step 312 is that the home position switch 125 is on (316), andsubsequently, in Step 318, judgment is made as to whether the bucket isclosed at the normal position or not, namely, whether the load switch120 is on or not. When the load switch 120 is not on, the disc motor 12stops (320) as shown in FIG. 6B, and the flow is returned to theoriginal routine. Subsequently, when the bucket 102 is closed at thenormal position, namely, the load switch is turned on (322), judgment ismade whether the forward switch 5 or the reverse switch 6 is on or notin Step 324. When it is judged that the forward switch 5 and the reverseswitch 6 are off (326), the disc motor 12 stops (320) and the flow isreturned to the original routine. Subsequently, when it is judged thatthe forward switch 5 or the reverse switch 6 is on (328) in Step 324,the rotary magnetic recording-reproducing apparatus gives a warning(330). The logical conditions of the switches in the flow 328 are shownbelow. (Hereinafter, similarly, descriptions will be successively madein FIGS. 6A to 6E)

    ______________________________________                                        Pack   HP     Load     FWD   REV  TR No. DISPLAY                              ______________________________________                                                               1     0                                                0      --     1                   --                                                                 0     1                                                ______________________________________                                    

This warning processing may have various modes. For stance, a LEDwarning lamp 8 may be turned on, the screen may be flashingly displayed,a number display may be flashingly displayed, and a waring sound may beissued. Or, the bucket 102 may be opened to inform the operator of anunloaded state. During this waring processing (330), the disc motor 12is stopped (320). As explained above, when the forward switch 5 or thereverse switch 6 is pressed in the state where the disc pack 200 is notinserted into the bucket 102, the warning is given. In consequence, themagnetic head 26 is not moved when the pack is not inserted.

Next, in the rotary magnetic recording-reproducing apparatus accordingto the present invention, when the magnetic head 26 is positioned in oneand the same track of the magnetic disc continuously for 18 min, awarning is issued, whereby the magnetic disc is automatically stopped orthe magnetic head 26 is shunted to the outside of the recording region.Description will now be given of this warning processing . Firstly, inStep 332 of FIG. 6A, when it is judged that the magnetic head 26 isreproducing continuously for 18 min on one and the same track by that a18 minute timer is set at zero (334), judgment is made as to whether theforward switch 5 or the reverse swtich 6 is on or not in Step 336. Whenit is judged that the forward switch 5 or the reverse switch 6 is off(338) in Step 336, the warning processing 330 similar to the one asexplained above is performed. When the operator is informed of anabnormal condition by the above-described warning processing 330 andturns on the forward switch 5 or the reverse switch 6 (340), the 18minute timer is reset, and the flow scans the original routine again. Inthe rotary magnetic recording-reproducing apparatus, when the magnetichead is positioned on one and the same track 18 min or more, a warningis issued to inform the operator of an abnormal condition, whereby themagnetic disc is automatically stopped or the magnetic head is shuntedto the outside of the recording region, so that the tracks of themagnetic disc can aboid being damaged.

Subsequently, when it is judged that the bucket 102 is not closed at thenormal position in Step 344 of FIG. 6B (346), the disc motor 12 remainsstopped (320).

Furthermore, when it is judged that the bucket 102 is closed at thenormal position (348) in Step 334, the disc motor 12 is rotated (350).

Next, in the rotary magnetic recording-reproducing apparatus accordingto the present invention, the initial operation to be describedhereunder will be performed. More specifically, when it is judged thatthe initial operation is performed in Step 352, i.e. the flag is zero(354), judgment is made as to whether the home position switch is on ornot in Step 356. When it is judged that the home position switch is off(358) in Step 356, the magnetic head 26 is fed in the reverse direction(360) and transferred toward the home position switch 125. When, beforelong, the magnetic head 26 is positioned at the home position and it isjudged that the home position switch 25 is on (362) in Step 356, theroutine proceeds to Step 364 where the initial tracking operation (orsensing of an unrecorded pack) is performed. In Step 364 where theinitial tracking operation is performed, the first track is sought bythe peak searching tracking operation, and, when this initial trackingoperation is completed, a flat INT showing the state of having processedthe initializing is set at 1 (366). The flow which has set the flat INTat 1 is returned to the original routine again, and in Step 352, theroutine directly proceeds to Step 370 of FIG. 6C, so that the routine ofthe initial operation is not scanned by the succeeding key scan.Furthermore, in the rotary magnetic recording-reproducing apparatus, inthe Step 364 where the initial tracking scanning is performed, theoperation of sensing the unrecorded pack is performed. Morespecifically, when an user of the rotary magnetic recordingreproducingapparatus inserts the unrecorded pack by mistake, the magnetic head 26searches all of the tracks, and, when it is judged that the recordingtrack is not present, a warning is issued to inform the user of the useof the unrecorded pack.

In the embodiment of the present invention, when a cleaning pack isloaded, similarly to the case of the unrecorded pack, the magnetic headmoves on all of the tracks and performs the work of cleaning themagnetic head. In this case, similarly to the case of the unrecordedpack, a warning to the effect that all of the tracks are moved through(the work of cleaning is completed) is given.

Description will here under be given of the setting of the timerreproduction of an image. The time duration of the timer reproduction ofthe image is set at eight sec as the basic time duration. This settingof the timer reproduction can be performed such that the timerreproducing time duration can be decreased by one sec by pressing theforward switch 5 several times with the display switch 7 being on, andfurther, the reproducing time duration of still image can be increasedby one sec by pressing the reverse switch 6 predetermined times, withthe display switch 7 being on. More specifically, when it is judged thatthe display switch is on (372) in Step 370, then judgment is made as towhether the forward switch 5 is on or not in Step 374. When it is judgedthat the forward switch 5 is on (376), judgment is made as to whetherthe forward switch 5 is turned on anew or remains pressed in Step 378.When it is judged that the forward switch 5 remains pressed (380), theflow returns to the original routine. When it is judged that the forwardswitch is turned on anew (382) in step 378, then judgment is made as towhether the timer counter is 1, i.e. the reproduction is performed for 1sec or not in Step 384. When it is judged that the timer counter is 1(386), then, how many times the forward key 5 may be pressed, theminimum reproducing time duration of 1 sec remains set and the flow isreturned to the original routine. Subsequently, when it is 24dged thatthe timer counter is not 1 (388), 1 sec is subtracted from the timercounter. More specificaly, when the timer duration is 5 sec reproducingtime duration for example, if the forward switch 5 is pressed anew, then1 is subtracted from the timer counter (390). In consequence, the timerduration is 4 sec reproducing time duration. As described above, Everytime the forward switch 5 is pressed with the display switch 7 being on,1 sec is subtracted from the timer counter. When the reproducing timeduration becomes 1 sec (386), the reproducing time duration set at 1 secis repeated as described above.

Subsequently, when the reverse switch 6 is turned on (396) with thedisplay switch 7 being on and the forward switch 5 being not pressed(392) in Step 394, judgment is made as to whether the reverse switch 6is turned on anew or remains pressed in Step 398. When it is judged thatthe reverse switch 6 remains pressed (400), the flow is returned to theoriginal routine. Subsequently, when it is judged that the reverseswitch 6 is turned on anew (402) in Step 398, judgment is made as towhether the timer counter is 9, i.e. an infinite rest time duration isset or not in Step 404. When it is judged that the infinite rest timeduration is set (406) in Step 404, how many times the reverse switch 6may be pressed, the infinite rest time duration does not change, wherebythe key scan scans the original routine. Subesquently, when it is judgedthat the timer counter is 8 and less in Step 404, such a process isperformed in Step 410 that 1 sec after another is added to the timercounter. More specifically, when 5 sec reproducing time duration is setby the timer counter 5 for example, 1 sec is added by pressing thereverse switch 6 one time, whereby the reproducing time duration becomes6 sec. Furthermore, if the reverse switch 6 is repeatedly pressed andthe timer counter becomes 9, the infinite reproducing time duration isset. As described above, in the rotary magnetic recording-reproducingapparatus according to the present invention, when the forward switch 5is pressed with the display switch 7 being on, the reproducing timeduration limited to 1 sec is subtracted, and, when the reverse switch 6is pressed determined times with the display switch 7 being on, thereproducing time duration can be increased by 1 sec.

Description will hereunder be given of a method of erasing the numberdisplay 49. According this method of erasing, the number display iserased by turning on the diaplay switch 7 during display, Morespecifically, when it is judged that the display switch 7 is turned onanew (414) in Step 412 of FIG. 6C and that this on-operation is doneduring display of the track number (418) in Step 416, the number displayis erased and the non-display mode is set (420). Subsequently, when theswitch 7 is turned on anew during the non-display (422), a 2 sec timeris reset (424), the track number is displayed for two sec after theswitch is removed from the hand (426), and the display mode is set(428). Furthermore, when it is judged that the display switch 7 is notturned on anew and remains pressed (430), the non-display mode is notset (432) in Step 431, the 2 sec timer is reset (424), the track numberis displayed (426) and the display mode is set(428).

Description will hereunder be given of a method of releasing the timerreproduction by use of the rotary magnetic recording-reproducingapparatus according to the present invention. The release of the timerreproduction is carried out by turning on the forward switch 5 or thereverse switch 6 during timer reproduction. More specifically, when thetimer reproduction is performed (436) in Step 434 of FIG. 6D, judgmentis made as to whether the forward switch 5 or the reverse switch 6 is onor not in Step 438. When it is judged that the forward switch 5 or thereverse switch 6 is not on (440), judgment is made as to whether thetimer is zero or not in Step 442. If the timer is zero, then thepredetermined timer reproducing time duration is set again (446), andthe tracking operation is performed toward the succeeding track (448).When it is judged that the forward switch 5 or the reverse switch 6 ison (450) in Step 438, judgment is made as to whether the forward switch5 or the reverse switch 6 is turned on anew in Step 460. When it isjudged that the forward switch 5 or the reverse switch 6 is not turnedon anew (462) in Step 460, the routine is returned to the normal one.When it is judged that the forward switch 5 or the reverse switch 6 isturned on anew (464), the timer reproduction is released (466). In otherwords, the timer counter is set to 9, stops and is cleared at the sametime (468). With this arrangement, a reproduced image is displayed onthe indicator 49 for the infinite reproducing time duration. Asdescribed above, in the rotary magnetic recording-reproducing apparatusaccording to the present invention, the timer reproduction can bereleased by turning on the forward switch 5 or the reverse switch 6during timer reproduction.

Description will hereunder be ginven of the search mode of the rotarymagnetic recording-reproducing apparatus according to the presentinvention. Firstly, when it is judged that the forward switch 5 or thereverse switch 6 is on (472) in Step 470 of FIG. 6E, then, judgment ismade whether the tracking is underway or not in Step 474. When thetracking is underway, the routine is returned to the original one (476),and, when the tracking is not underway, the track number display 49 iserased (478). Subsequently, judgment is made as to whether the forwardswitch 5 or the reverse switch 6 is turned on anew or not, and, when theforward switch 5 or the reverse switch 6 is turned on anew (482), thetracking operation is performed in Step 484, a 1 sec timer is reset andthe routine is returned to the original one, When the forward switch 5or the reverse switch 6 remains pressed (488) in Step 480, judgment ismade as to whether the 1 sec timer is zero or not in Step 490. When the1 sec timer is not zero (492), the routine is returned to the originalone. When it is judged that the 1 sec timer is zero, i.e. the forwardswitch 5 or the reverse switch 6 remains pressed for 1 sec or more, the1 sec timer stops in the time counter, simultaneously, the 1 sec timeris cleared (494), and subsequently, the tracking scanning is performed(496). Upon completion of the tracking operation, the track number 49 isdisplayed for 2 V time duration, i.e. 1/30 sec (498). As describedabove, in the above embodiment, the screen can be successively fed fromone frame to another at high speed by continuously pressing the forwardswitch 5 or the reverse switch 6, and moreover, the track number 49 canbe displayed for 2 V time duration (1/30 sec) during which the screencan be caught by eyesight, so that the necessary screen can be searched.

Step 500 of the time counter-processing, which is used in the aboveroutine includes the 1 sec timer, 2 sec timer, 18 min timer and timesetting timer (TIMER).

FIGS. 7A to 7F are the flow charts operationally showing the sub-routineprocessing in the embodiment of the present invention.

Here, FIGS. 6A to 6E are the flow charts wherein the fact that whatinterruptions can be applied by the respective keys is explained, mainlytaking up the conditions of the respective keys read in by the key scanperformed in 1V cycle. However, FIGS. 7A to 7E, which are used forexplanation, are the flow charts expaining the functions of theapparatus, mainly taking up the operation of the apparatus, and flags,etc. in the flows are merely used for the convenience's sake.

Description will firstly be given of the routine for searching the firsttrack in the initial operation with reference to 7A to 7E. When thepower switch 2 is on or the load switch 120 in on (500), judgment ismade as to whether the display switch is on or not in Step 502. When thepower source switch 2 or the load switch 120 and the display switch 7are pressed simultaneously (504), a special mode is set (506) and thenumber display is indicated as an absolute address (namely, an addressis set in accordance with the number of moving distances of the head).When the display switch 7 is not on (508) in the Step 502, a normal modeis set (510), and the number display is indicated as a relative address(namely, only the number of the tracks recorded is counted and thistrack is addressed). The operation up to this corresponds to the resetof the Step 300 of FIG. 6A. Subsequently, RAM clear is made (512),wherby the memory accumulated so far is cleared. Then, the key scan ismade by pulses rotated in 1V cycle (514), and judgment is made as towhether the home position switch 125 is on or not (516). Operations tobe described hereunder correspond to the initial tracking operationwhere the interruption is applied from the Step 352 of FIG. 6B and theoperation of sensing the unrecorded pack. When the home position switch125 is not on (518), the magnetic head 26 is moved by one unit (100 μm)in the reverse direction. This operation is repeated until the homepositions witch 125 is turned on. When the home position switch 125 isturned on (524), the magnetic head 26 is moved a predetermined distancein the forward direction (526), the number of head moving distances iscounted (528), and judgment is made as to whether the movement of 60track widths counted from the home position is made or not in Step 530.When the movement of 60 track widths counted from the home position isnot made in the Step 530, an A/D value of an wave detection output of anenvelope is read (536), and further, judgment is made as to whether theA/D value reaches a predetermined value or more or not in Step 538. Whenthe A/D value is less than the predetermined value (540), which meansthat the head 26 is not moved to the first recording track, the head 26is moved in the forward direction again (526), and the abovedescribedoperation is repeated until the A/D value reaches the predeterminedvalue or more, i.e. the head 26 reaches the first recording track. Whenthe movement of 60 track widths is made in this operation (532), it isjudged that the unrecorded pack is present, this fact is warned, themuting is made and the movement of the head 26 is stopped (534). When itis judged that the A/D value reaches the predetermined value or more inthe Step 538, the non-recorded flag is reset and the track number is setto 1 (542). Further, in this No. 1 track, the tracking is performed bythe peak searching servo (544), whereby a peak value is sought, and thetrack number is displayed for two sec (546). As described above, the No.1 track can be sought in the initial operation.

The foregoing is the explanation of the initial operation.

Description will hereunder be given of the operations of successivelysearching the tracks of No. 2 and so forth. Further, description will begiven of the operation in the case where there are continuously presenttwo or more unrecorded or dropout tracks in the above-mentioned searchoperations with reference to FIGS. 7C to 7D. In the embodiment of thepresent invention, when there are continuously present two or moreunrecorded or dropout tracks, it is judged that all of the furthertracks belong to an unrecorded portion, where by the warning is issued.Firstly, when the search is made from the first track to the secondtrack, judgment is made as to whether the forward switch 5 is on or notin Step 548, and, when it is judged that the forward switch 5 is on, thetrack number display is turned off (550), and subsequently, judgment ismade as to whether the track number display is 50 or more or not in Step552. When the track number display is less than 50, judgment is made asto whether the number of moving distances of the head, which is countedfrom the home position is 60 or more or not in Step 554. When the numberof moving distances of the head is less than 60, judgment is made as towhether the non-record flag is 1 or not in Step 556. This non-recordflag is one showing whether the track subjected to the trackingoperation in the above operation is an unrecorded track or a dropouttrack. When the non-record flag is 1, the track number is not added whenthe succeeding tracking operation is started, and only the recordedtracks are counted by the non-record flag. Since the non-record flag isset to zero in the Step 542 of the searching operation of No. 1 track,the non-record flag is not 1. In consequence, 1 is added to the tracknumber, further, 1 is added to the number of moving distances of thehead, which is counted from the home position (560), the magnetic head26 is moved by 24 pulse widths (100 μm) in the forward direction (562),and the A/D value of the wave detection output of the envelope is readin (580).

On the other hand, when the forward switch 5 is not pressed (564) in theStep 548, judgment is made as to whether the reverse switch 6 is pressedor not in Step 566. When it is judged that the reverse switch 6 ispressed in Step 566, the track number display switch is turned off(568), and subsequently, judgment is made as to whether the track numberis less than 1 or not in Step 570. When the track number is 1 or more,judgment is made as to whether the non-record flag is 1 or not in Step572. When the non-record flag is zero, 1 is subtracted from the tracknumber display (574), and further, 1 is subtracted from the number ofmoving distances of the head which is counted from the home position.Subsequently, the magnetic head 26 is moved by 24 pulse widths (100 μm)in the reverse direction (578), and the A/D value of the wave detectionoutput of the envelope is read in (580).

Description will now be given of the case where the forward switch 5 isturned on in order to search from the first track to the second track asdescribed above. Judgment is made as to whether the A/D value is apredetermined value or more or not in Step 582. When the A/D value isthe predetermined value or more, the tracking operation is performed bythe peak searching servo (584), and further, judgment is made as towhether the forward switch 5 or the reverse switch 6 is pressed in thesearch mode, i.e. remains pressed for 1 sec or more in Step 586. When nosearch mode is present, judgment is made as to whether the display modeis present or not in Step 588. When the display mode is present, thetrack number is displayed for two sec (590). subsequently, the routineis returned to the Step 548 by a skip number ○11 , and theabove-described operation is repeated, whereby the magnetic head 26moves until it reaches 50 tracks, or it moves by 60 track widths countedfrom the home position switch. Additionally, when it is judged that thesearch mode is present (592) in Step 586, the magnetic head 26 is movedwhile the track number is being displayed for 2 V time duration (1/30sec) (594).

Description will hereunder be given of the case where an unrecordedtrack is continuously present in the track search after theabove-described second track with reference to FIG. 7E. Firstly, whenthe A/D value is less than the predetermined value, i.e. an unrecordedtrack is present in Step 582, judgment is made as to whether the specialmode is present or not in Step 596, and, when the special mode ispresent (598), the routine is returned to the original one. When thespecial mode is not present (600), judgment is made as to whether thenon-record flag is 1 or not in Step 602, to which the routine proceedsthrough a skip number ○13 . Since the non-record flag is set to zero asdescribed above, it is judged that the non-record flag is not zero(604), and then, the non-record flag is set to 1 here (606).Subsequently, judgment is made as to whether the track number is 50 ormore or not in Step 608, and, when the track number is less than 50,judgment is made as to whether the number of moving distances of thehead, which is counted from the home position, is 60 or more or not inStep 610. When the number of moving distance of the head is less than 60(612), judgment is made as to whether the forward feed is to beperformed or not in Step 614. When it is judged that the forward feed isto be performed (616) in the Step 614, the routine proceeds through askin number ○14 , and then, judgment is made again as to whether thetrack number is 50 or more or not in Step 552. When the track number isless than 50 in the Step 552, judgment is made as to whether the numberof moving distances of the head is 60 or more in Step 554. When thenumber of moving distances of the head is less than 60, judgment is madeas to whether the non-record flag is 1 or not in Step 556. Since thenon-record flag is set to 1 as described above (606), it is judged thatthe non-record flag is 1 (618) in Step 556, an addition of 1 to thetrack number display (558) is by-passed, and 1 is added to the number ofmoving distances of the head (560).

Subsequently, the head 26 is fed by 100 μm again (562), and the A/Dvalue of the wave detecting output of the envelope is read (580). Whenthe A/D value is the predetermined value or more, it is judged that theunrecorded track is only one, and the tracking operation and the tracknumber display are performed in accordance with the operations of 584and so forth. Here, when the A/D value is less than the predeterminedvalue (600), the routine proceeds through the skip number ○13 , and,judgment is made as to whether the non-record flag is 1 or not in Step602. Since the non-record flag is set to 1 as described above, it isjudged that the non-record flag is set to 1 (620), and then, judgment ismade as to whether the moving direction is forward or not in Step 622.Since the moving direction is set to forward, the routine proceeds to aflow 624 and the moving direction is switched from forward to reverse(626). Thereafter, judgment is made as to whether forward or not in Step614. Since the moving direction is set to reverse (636) as describedabove, the routine is returned to a skip number ○15 , and judgment ismade as to whether the track number is 1 or not in Step 570. Since thetrack number is not less than 1, the routine proceeds to Step 572, andjudgment is made as to whether the non-record flag is 1 or not. Sincethe non-record flag is set to 1, a subtraction of 1 from the tracknumber display (574) is by-passed, and then, a substraction of thenumber of moving distances of the head (576) is made is a flow 628.Subsequently, the head is moved by 100 μm in the reverse directionf(578), and the A/D value of the wave detection output of the envelopeis read (580). However, since the magnetic head in this position islocated at a first unrecorded track position, the A/D value is not thepredetermined value or more, which is judged in Step 582, the routineproceeds through Step 596 and flow 600, further, proceeds through theskip number ○13 , and again, judgment is made whether the non-recordflag is 1 or not in Step 602. Since the non-record flag is 1 (620),subsequently, judgment is made as to whether the moving direction isforward or not in Step 622. Since the moving direction is not forward(630), subsequently, the non-record flag is reset to zero (632), andfurther, the number of moving distances of the head is set to 61 (634).

When assumptionis made that the record is made up to 30th track with theabove-described arrangement, if 31st track and 32nd track are unrecordedtracks, the 31st track is set to the number 61 of moving distances ofthe head, which is counted from the home position, and the 30th track asbeing the final recording track is set to the number 60 of movingdistances of the head, which is counted from the home position. Inconsequence, in the control device 60, it is judged that the tracksdownward therefrom are out of the recording region. Subsequently,judgment is made as to whether the moving direction is forward or not inStep 614. Since the moving direction is set in the reverse direction(636), the routine proceeds through the skip number ○15 , subsequently,judgment is made as to whether the track number is less than 1 or not inStep 570. Since the track number is 1 or more, further, judgment is madeas to whether the non-record flag is 1 or not in the succeeding Step572. Since the non-record flag is set to zero (632), 1 is subtractedfrom the truck number (574), subsequently, 1 is subtracted from thenumber of moving distances of the head (576), and subsequently, themagnetic head is moved by 100 μm in the reverse direction (578). Then,the A/D value of the wave detection output of the envelope is read.Since the magnetic head 26 is fed on the two unrecorded tracks in thereverse direction and positioned on the final recording track at thistime, it is judged that the A/D value is the predetermined value ormore, and again, the peak searching operation (584) and the track numberdisplay (590) are repeated in accordance with the tracking opertionsfrom 584 on. Further, when forward switch 5 is pressed in this state,because the number of moving distances of the head is set to 60 asdescribed above, it is judged that the number of moving distances of thehead is 60 or more (644) in Step 554, whereby a warning processing ismade (642). This warns the fact that, in spite of that the magnetic head26 is positioned on the final track, the forward switch 5 is pressed.This setting of this final track is stored in the RAM unless theabove-described initial operation is performed.

In the above embodiment, when the forward switch 5 is pressed with thetrack numver being at a position of 50 (548) for example, it is judgedthat the track number is 50 or more (638) in Step 552, and the warningprocessing is performed (642). On the contrary, when the reverse switch6 is pressed in No. 1 track (566), it is not judged that the tracknumber is 1 or more (640) in Step 570, and the warning processing isperformed (642) similarly to the above.

The flows explained above correspond to the tracking sub-routines 484and 496 as shown in FIG. 6E out of the interruption flows in FIGS. 6A to6E.

It should be understood, however, that there is no invention to limitthe intention to the specific forms disclosed, but on the contrary, theinvention is to cover all modifications, alternate constructions andequvalents falling within the spirit and scope of the invention asexpressed in the appended claim.

What is claimed is:
 1. A rotary magnetic recording-reproducing apparatus comprising: a magnetic head for reading signals from a plurality of tracks each of said tracks formed into a locus in which relative positions of a leading end and a tail end of a recording coincide with each other on a rotary magnetic recording medium; head moving means for transferring said magnetic head onto a selected one of the tracks; and control means for controlling said head moving means so that the magnetic head is located on the selected track; andaddress setting means wherein absolute addresses and relative addresses are simultaneously used to make the addressing from the first track to the final track.
 2. A rotary magnetic recording-reproducing apparatus as set forth in claim 1, wherein said absolute addresses are set in association with pulse signals delivered to a motor for driving said magnetic head.
 3. A rotary magnetic recording-reproducing apparatus as set forth in claim 1, wherein said relative addresses are set on the basis of the presence of detection of an envelope of a track by said magnetic head.
 4. A rotary magnetic recording-reproducing apparatus comprising:a recording medium having a plurality of recording tracks formed thereon; a magnetic head for reading signals from said tracks of said recording medium; positioning means for positioning said magnetic head onto a selected recording track; computer memory means, said computer memory means having a plurality of memory locations defined therein; wherein an address is assigned to each of said memory locations; and address setting means for assigning both absolute addresses and relative addresses to said recording tracks so as to define the absolute and relative position of said recording tracks.
 5. A rotary magnetic recording-reproducing apparatus as set forth in claim 4, wherein said absolute addresses are set in association with pulse signals delivered to a motor for driving said magnetic head.
 6. A rotary magnetic recording-reproducing apparatus as set forth in claim 4, wherein said relative addresses are set on the basis of the presence of detection of an envelope of a track by said magnetic head. 